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Observation of the keto tautomer of D-fructose in D2O using 1H NMR spectroscopy
No full textD-Fructose was analysed by NMR spectroscopy and previously unidentified 1H NMR resonances were assigned to the keto and a-pyranose tautomers. The full assignment of shifts for the various fructose tautomers enabled the use of 1H NMR spectroscopy in studies of the mutarotation (5–25 C) and tautomeric composition at equilibrium (5–50 C). The mutarotation of b-pyranose to furanose tautomers in D2O at a concentration of 0.18 M was found to have an activation energy of 62.6 kJ mol 1. At tautomeric equilibrium (20 C in D2O) the distribution of the b-pyranose, b-furanose, a-furanose, a-pyranose and the keto tautomers was found to be 68.23%, 22.35%, 6.24%, 2.67% and 0.50%, respectively. This tautomeric composition was not significantly affected by varying concentrations between 0.089 and 0.36 M or acidification to pH 3. Upon equilibrating at 6 temperatures between 5 and 50 C there was a linear relationship between the change in concentration and temperature for all forms.
Theoretical studies of parent 1- ,2- , 3-pyrazolines and their methylated derivatives
No full textA theoretical study of the minima of 1-, 2-, and 3-pyrazolines as well as some methyl derivatives was performed using B3LYP/6-311++G(d,p) and CCSD(T) calculations. Conformation, tautomerism, basicity, protonation as well as NMR properties have been computationally studied. In general, the agreement with the available experimental results is excellent, highlighting the predictive potential of this type of study in the consideration of new compounds.
'tieredScreen' - Layered virtual screening tool for the identification of novel estrogen receptor alpha modulators
No full textA novel tiered Structure-Based (SB) Virtual Screening (VS) workflow called tieredScreen was designed and implemented. The automated protocol utilises diverse computational tools in a synergistic manner to reduce false positives and increase the likelihood of converging on putative active molecules. The performance of the novel VS workflow was validated using the Directory of Useful Decoys (DUD) Estrogen Receptor α (ERα) antagonist dataset, and successfully deployed for the identification of novel antagonists of ERα from a screening collection of ca. 160000 commercially available compounds. As well as yielding nanomolar (nM) active ligands identified previously through a docking only protocol, from a selection of eight virtual hits suggested by tieredScreen, four novel nM ERa binding chemotypes were identified and biologically validated – demonstrating the applicability of a tiered intervention for virtual screening.
Synthesis and serotonin transporter activity of sulphur-substituted a-alkyl phenethylamines as a new class of anticancer agents
No full textThe discovery that some serotonin reuptake transporter (SERT) ligands have the potential to act as pro-apoptotic agents in the treatment of cancer adds greatly to their diverse pharmacological application. 4-Methylthioamphetamine (MTA) is a selective ligand for SERT over other monoamine transporters. In this study, a novel library of structurally diverse 4-MTA analogues were synthesised with or without N-alkyl and/or C-α methyl or ethyl groups so that their potential SERT-dependent antiproliferative activity could be assessed. Many of the compounds displayed SERT-binding activity as well as cytotoxic activity. While there was no direct correlation between these two effects, a number of derivatives displayed anti-tumour effects in lymphoma, leukaemia and breast cancer cell lines, showing further potential to be developed as possible chemotherapeutic agents.
A review of the numerical modelling of salt mobilization from groundwater-surface water interactions
No full textSalinization of land and water is a significant challenge in most continents and particularly in arid and semi arid regions. The need to accurately forecast surface and groundwater interactions has promoted the use of physically based numerical modelling approaches in many studies. In this regard, two issues can be considered as the main research challenges. First, in contrast with surface water, there is generally less observed level and salinity data available for groundwater systems. These data are critical in the validation and verification of numerical models. The second challenge is to develop an integrated surface groundwater numerical model that is capable of salt mobilization modelling but which can be validated and verified against accurate observed data. This paper reviews the current state of understanding of groundwater and surface water interactions with particular respect to the numerical modelling of salt mobilization. 3D physically based fully coupled surface subsurface numerical model with the capability of modelling density dependent, saturated unsaturated solute transport is an ideal tool for groundwater surface water interaction studies. It is concluded that there is a clear need to develop modelling capabilities for the movement of salt to, from, and within wetlands to provide temporal predictions of wetland salinity which can be used to assess ecosystem outcomes.
Profile of the complementary and alternative medicine workforce across Australia, New Zealand, Canada, United States and United Kingdom
No full textConclusions: This work has helped shape current understandings of the CAM workforce. In doing so, it will help to inform the training and continuing education needs of the evolving CAM workforce, and further, ensure the provision of a competent CAM workforce to service the needs of consumers. Addressing the many limitations of existing data sources will assist in meeting these needs.
Parvifloranines A and B, two 11-carbon alkaloids from Geijera parviflora
No full textTwo novel alkaloids (parvifloranines A and B), possessing an unusual 11-carbon skeleton linked with amino acids, were isolated from Geijera parviflora , an endemic Australian Rutaceae. Their structures were elucidated by extensive spectroscopic measurements including 2D NMR analyses. Parvifloranine A was found to be a mixture of two enantiomers, (S)-1 and (R)-1 , in a ratio of 1:4, based on their separation using a chiral column. Parvifloranine B is also believed to be a mixture of enantiomers. Proposed biosynthetic pathways are discussed. Parvifloranine A inhibited the synthesis of nitric oxide in LPS-stimulated RAW 264.7 macrophages with an IC 50 value of 23.4 μM.
Using a web-based survey tool to undertake a Delphi study : application for nurse education research
No full textConclusions: High response rates and an increased level of data quality were achieved in this study using web-survey software and the process was efficient and user-friendly. However, when considering online survey software, it is important to match the research design with the computer capabilities of participants and recognize that ethical review guidelines and processes have not yet kept pace with online research practices.
Snakes and ladders : the barriers and facilitators of elective hip- and knee-replacement surgery in Australian public hospitals
No full textConclusions: Given the complexity of the elective surgery system, it is not surprising that single-item reforms have not created lasting reductions in waiting times. Multifaceted, whole-system reforms may be more successful.
Wine tourism experience effects of the tasting room on consumer brand loyalty
No full textThis study's overall purpose was to contribute to the wine tourism knowledge base regarding the impact of the winery tasting room experience on consumer wine brand loyalty. A total of 108 surveys were conducted at wineries in the Barossa Wine Region in South Australia in an exploratory study. The study's main contribution is the development of three scales to operationalize the research, namely, Wine Brand Loyalty, Winery Tasting Room Initial Perception, and Winery Tasting Room Actual Experience Scales, and to determine what influence initial perceptions combined with the actual tasting room experiences have on brand attitudes and eventually on brand loyalty. The brand loyalty scale returned a Cronbach's alpha of 0.802. It was confirmed that wine quality has a significant impact on brand attitudes. A higher level of perceived wine value increased brand attitudes, whereas positive brand attitudes increase the likelihood of future purchase intentions. The overall tasting room experience is significantly correlated to brand attitudes. There is a strong correlation between the winery tasting room experience and brand loyalty, proving that consumers who have an enjoyable and memorable experience are more likely to buy the wine again and/or promote the wine brand to others.